Is o la t e d Tra n s fo rm e r Drive r
fo r P CMCIA Ap p lic a t io n s
MAX845
Table 2. Rectifier Topology Trade-Offs
Table 3. Suggested Capacitor Suppliers
CAPACITOR
SUPPLIER
Matsuo
USA Phone: (714) 969-2491
FAX: (714) 960-6492
TOPOLOGY
ADVANTAGE
DISADVANTAGE
Low-ESR 267 Series
Murata Erie
USA Phone: (800) 831-9172
FAX: (404) 436-3030
• Only 3 external
components
Ceramic
2-Diode
Push/Pull
(Figure 11a)
• More turns on
transformer
• Low output ripple
• Single diode drop
Sprague Electric Co.
USA Phone: (603) 224-1961
FAX: (603) 224-1430
Very Low-ESR 595D/293D
Series
• 5 external
components
• Simpler transformer
winding requirements
4-Diode
Bridge
(Figure 11b)
• Higher cost
• Low output ripple
• 2 diode drops
• 4 external
components
Voltage
Doubler
(Figure 11c)
• Fewest turns on
transformer
• Higher output
ripple
• 2 diode drops
___________________Ch ip To p o g ra p h y
D1
D2
0. 085"
(2. 159mm)
GND1
GND2
FS
V
CC
SD
0. 058"
(1. 4732mm)
SUBSTRATE CONNECTED TO V
CC
TRANSISTOR COUNT: 31
______________________________________________________________________________________ 15
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
